I was curious to see if the rather uninspiring pgbench performance obtained from a Sun 280R (see General: ATA Disks and RAID controllers for database servers) could be improved if more time was spent tuning.
With the help of a fellow workmate who is a bit of a Solaris guy, we decided to have a go.
The major performance killer appeared to be mounting the filesystem with the logging option. The next most significant seemed to be the choice of sync_method for Pg - the default (open_datasync), which we initially thought should be the best - appears noticeably slower than fdatasync.
We also tried changing some of the tuneable filesystem options using tunefs - without any measurable effect.
Are Pg/Solaris folks running with logging on and sync_method default out there ? - or have most of you been through this already ?
Pgbench Results (no. clients and transactions/s ) :
Setup 1: filesystem mounted with logging
No. tps ----------- 1 17 2 17 4 22 8 22 16 28 32 32 64 37
Setup 2: filesystem mounted without logging
No. tps ----------- 1 48 2 55 4 57 8 62 16 65 32 82 64 95
Setup 3 : filesystem mounted without logging, Pg sync_method = fdatasync
No. tps ----------- 1 89 2 94 4 95 8 93 16 99 32 115 64 122
Note : The Pgbench runs were conducted using -s 10 and -t 1000 -c 1->64, 2 - 3 runs of each setup were performed (averaged figures shown).
Mark
---------------------------(end of broadcast)--------------------------- TIP 1: subscribe and unsubscribe commands go to [EMAIL PROTECTED]
